| Indication |
For the treatment of pulmonary tuberculosis. |
| Pharmacodynamics |
Rifapentine is an antibiotic that inhibits DNA-dependent RNA
polymerase activity in susceptible cells. Specifically, it interacts
with bacterial RNA polymerase but does not inhibit the mammalian enzyme.
It is bactericidal and has a very broad spectrum of activity against
most gram-positive and gram-negative organisms (including Pseudomonas
aeruginosa) and specifically Mycobacterium tuberculosis. Because of
rapid emergence of resistant bacteria, use is restricted to treatment of
mycobacterial infections and a few other indications. Rifampin is well
absorbed when taken orally and is distributed widely in body tissues and
fluids, including the CSF. It is metabolized in the liver and
eliminated in bile and, to a much lesser extent, in urine, but dose
adjustments are unnecessary with renal insufficiency. |
| Mechanism of action |
Rifapentine has shown higher bacteriostatic and bactericidal
activities especially against intracellular bacteria growing in human
monocyte-derived macrophages. Rifapentine inhibits DNA-dependent RNA
polymerase in susceptible strains of M. tuberculosis. Rifapentine acts
via the inhibition of DNA-dependent RNA polymerase, leading to a
suppression of RNA synthesis and cell death. |
| Absorption |
Rapidly and well absorbed from the gastrointestinal tract. |
| Volume of distribution |
|
| Protein binding |
97.7% (bound to plasma proteins) |
| Metabolism |
Hepatic |
| Route of elimination |
Following a single 600 mg oral dose of radiolabeled rifapentine to
healthy volunteers (n=4), 87% of the total 14C rifapentine was
recovered in the urine (17%) and feces (70%). |
| Half life |
Not Available |
| Clearance |
- Apparent Oral cl=2.51 +/- 0.14 L/h [Male tuberculosis patients who
received 600 mg rifapentine in combination with isoniazid, pyrazinamide
and ethambutol]
- Apparent Oral cl=1.69 +/- 0.41 L/h [Female tuberculosis patients
who received 600 mg rifapentine in combination with isoniazid,
pyrazinamide and ethambutol]
|
| Toxicity |
Not Available |
